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Brain Sciences Jan 2024Existing evidence suggests that developmental prosopagnosia (DP) is a surprisingly prevalent condition, with some individuals describing lifelong difficulties with...
Existing evidence suggests that developmental prosopagnosia (DP) is a surprisingly prevalent condition, with some individuals describing lifelong difficulties with facial identity recognition. Together with case reports of multiple family members with the condition, this evidence suggests that DP is inherited in at least some instances. Here, we offer some novel case series that further support the heritability of the condition. First, we describe five adult siblings who presented to our lab with symptoms of DP. Second, for the first known time in the literature, we describe a pair of adult identical twins who contacted us in the belief that they both experience DP. The condition was confirmed in three of the five siblings (with minor symptoms observed in the remaining two) and in both twins. Supplementary assessments suggested that all individuals also experienced some degree of difficulty with facial identity perception, but that object recognition was preserved. These findings bolster the evidence supporting the heritability of DP and suggest that it can be a specific impairment in some cases.
PubMed: 38248264
DOI: 10.3390/brainsci14010049 -
Neuroscience and Biobehavioral Reviews Mar 2024Face-selective regions in the human ventral occipito-temporal cortex (VOTC) have been defined for decades mainly with functional magnetic resonance imaging. This... (Review)
Review
Face-selective regions in the human ventral occipito-temporal cortex (VOTC) have been defined for decades mainly with functional magnetic resonance imaging. This face-selective VOTC network is traditionally divided in a posterior 'core' system thought to subtend face perception, and regions of the anterior temporal lobe as a semantic memory component of an extended general system. In between these two putative systems lies the anterior fusiform gyrus and surrounding sulci, affected by magnetic susceptibility artifacts. Here we suggest that this methodological gap overlaps with and contributes to a conceptual gap between (visual) perception and semantic memory for faces. Filling this gap with intracerebral recordings and direct electrical stimulation reveals robust face-selectivity in the anterior fusiform gyrus and a crucial role of this region, especially in the right hemisphere, in identity recognition for both familiar and unfamiliar faces. Based on these observations, we propose an integrated theoretical framework for human face (identity) recognition according to which face-selective regions in the anterior fusiform gyrus join the dots between posterior and anterior cortical face memories.
Topics: Humans; Prosopagnosia; Temporal Lobe; Facial Recognition; Recognition, Psychology; Magnetic Resonance Imaging; Pattern Recognition, Visual; Brain Mapping; Photic Stimulation
PubMed: 38191080
DOI: 10.1016/j.neubiorev.2024.105535 -
Applied Neuropsychology. Adult Nov 2023Language impairments have not yet been fully explored in native Arabic speakers with semantic dementia (SD). The aim of this paper is to describe the impairments in...
INTRODUCTION
Language impairments have not yet been fully explored in native Arabic speakers with semantic dementia (SD). The aim of this paper is to describe the impairments in language in two Saudi Arabians with SD and to determine if their word reading within a sentence context would result in incorrect responses.
METHODS
Two patients with semantic dementia (one with right > left and the other with left > right temporal involvement) underwent a reading assessment in Arabic. Patients were asked to read a series of words within a sentence context in which the correct reading of the word was dependent on the context of the sentence. Thirty-four sentences were designed in which 17 Arabic homographs were used. The same homograph would occur in two separate sentences, in which the pronunciation and meaning would differ between sentences. Patients were also assessed using five other sentences that contained irregular pronouns of high frequency. Eighteen healthy controls were used as reference.
RESULTS
Both patients made errors in reading the target Arabic homographs; this was more pronounced in the patient with left > right variant of SD. The patient with right > left variant of SD also suffered from prosopagnosia.
CONCLUSION
Correct reading of Arabic words within the sentence context may be impaired from semantic language impairments in semantic dementia. The role of comprehension in the correct reading of words in Arabic sentences is important.
PubMed: 37917946
DOI: 10.1080/23279095.2023.2276436 -
Brain Sciences Sep 2023Faces play a crucial role in social interactions. Developmental prosopagnosia (DP) refers to the lifelong difficulty in recognizing faces despite the absence of obvious... (Review)
Review
Faces play a crucial role in social interactions. Developmental prosopagnosia (DP) refers to the lifelong difficulty in recognizing faces despite the absence of obvious signs of brain lesions. In recent decades, the neural substrate of this condition has been extensively investigated. While early neuroimaging studies did not reveal significant functional and structural abnormalities in the brains of individuals with developmental prosopagnosia (DPs), recent evidence identifies abnormalities at multiple levels within DPs' face-processing networks. The current work aims to provide an overview of the convergent and contrasting findings by examining twenty-five years of neuroimaging literature on the anatomo-functional correlates of DP. We included 55 original papers, including 63 studies that compared the brain structure (MRI) and activity (fMRI, EEG, MEG) of healthy control participants and DPs. Despite variations in methods, procedures, outcomes, sample selection, and study design, this scoping review suggests that morphological, functional, and electrophysiological features characterize DPs' brains, primarily within the ventral visual stream. Particularly, the functional and anatomical connectivity between the Fusiform Face Area and the other face-sensitive regions seems strongly impaired. The cognitive and clinical implications as well as the limitations of these findings are discussed in light of the available knowledge and challenges in the context of DP.
PubMed: 37891769
DOI: 10.3390/brainsci13101399 -
Cureus Sep 2023Prosopagnosia describes the inability to recognize others by their faces, which may be hereditary or acquired. Acquired cases result from intracranial lesions such as...
Prosopagnosia describes the inability to recognize others by their faces, which may be hereditary or acquired. Acquired cases result from intracranial lesions such as intracranial hemorrhage or ischemia. This case demonstrates acquired prosopagnosia secondary to an intracranial hemorrhage and thus exemplifies the importance of early symptom recognition for appropriate diagnosis and management. A 58-year-old female presented to the emergency department with a chief complaint of the worst headache of her life along with nausea and vomiting. She also reported that she was unable to recognize her children in photos and although she knew her husband was with her, she did not recognize his face. Physical examination revealed no focal motor deficits. Computed tomography angiography of the brain revealed intracerebral hemorrhage of the right occipital lobe. Acquired prosopagnosia can be the only presenting symptom of intracranial pathology. It is most commonly caused by intracranial hemorrhage, as shown in this case report. This demonstrates a unique symptom of posterior circulation strokes that are commonly misdiagnosed in the emergency department.
PubMed: 37842404
DOI: 10.7759/cureus.45128 -
Neuropsychologia Nov 2023Neuroimaging and intracranial electrophysiological studies have consistently shown the largest and most consistent face-selective neural activity in the middle portion...
Neuroimaging and intracranial electrophysiological studies have consistently shown the largest and most consistent face-selective neural activity in the middle portion of the human right lateral fusiform gyrus ('fusiform face area(s)', FFA). Yet, direct evidence for the critical role of this region in face identity recognition (FIR) is still lacking. Here we report the first evidence of transient behavioral impairment of FIR during focal electrical stimulation of the right FFA. Upon stimulation of an electrode contact within this region, subject CJ, who shows typical FIR ability outside of stimulation, was transiently unable to point to pictures of famous faces among strangers and to match pictures of famous or unfamiliar faces presented simultaneously for their identity. Her performance at comparable tasks with other visual materials (written names, pictures of buildings) remained unaffected by stimulation at the same location. During right FFA stimulation, CJ consistently reported that simultaneously presented faces appeared as being the same identity, with little or no distortion of the spatial face configuration. Independent electrophysiological recordings showed the largest neural face-selective and face identity activity at the critical electrode contacts. Altogether, this extensive multimodal case report supports the causal role of the right FFA in FIR.
Topics: Female; Humans; Pattern Recognition, Visual; Prosopagnosia; Magnetic Resonance Imaging; Facial Recognition; Temporal Lobe; Electric Stimulation; Photic Stimulation; Brain Mapping
PubMed: 37839512
DOI: 10.1016/j.neuropsychologia.2023.108705 -
Autism Research : Official Journal of... Nov 2023Difficulties in various face processing tasks have been well documented in autism spectrum disorder (ASD). Several meta-analyses and numerous case-control studies have...
Difficulties in various face processing tasks have been well documented in autism spectrum disorder (ASD). Several meta-analyses and numerous case-control studies have indicated that this population experiences a moderate degree of impairment, with a small percentage of studies failing to detect any impairment. One possible account of this mixed pattern of findings is heterogeneity in face processing abilities stemming from the presence of a subpopulation of prosopagnosic individuals with ASD alongside those with normal face processing skills. Samples randomly drawn from such a population, especially relatively smaller ones, would vary in the proportion of participants with prosopagnosia, resulting in a wide range of group-level deficits from mild (or none) to severe across studies. We test this prosopagnosic subpopulation hypothesis by examining three groups of participants: adults with ASD, adults with developmental prosopagnosia (DP), and a comparison group. Our results show that the prosopagnosic subpopulation hypothesis does not account for the face impairments in the broader autism spectrum. ASD observers show a continuous and graded, rather than categorical, heterogeneity that span a range of face processing skills including many with mild to moderate deficits, inconsistent with a prosopagnosic subtype account. We suggest that pathogenic origins of face deficits for at least some with ASD differ from those of DP.
Topics: Adult; Humans; Autistic Disorder; Autism Spectrum Disorder; Recognition, Psychology; Facial Recognition; Prosopagnosia; Pattern Recognition, Visual
PubMed: 37740564
DOI: 10.1002/aur.3030 -
Behavioral Sciences (Basel, Switzerland) Aug 2023Children with prosopagnosia, also known as face blindness, struggle to recognize the faces of acquaintances, which can have a negative impact on their social... (Review)
Review
Children with prosopagnosia, also known as face blindness, struggle to recognize the faces of acquaintances, which can have a negative impact on their social interactions and overall functioning. This paper reviews existing research on interventions for children with prosopagnosia, including compensatory and remedial strategies, and provides a summary and comparison of their effectiveness. However, despite the availability of these interventions, their effectiveness remains limited and constrained by various factors. The lack of a widely accepted treatment for children with prosopagnosia emphasizes the need for further research to improve intervention strategies. Last, three future research directions were proposed to improve interventions for prosopagnosia, including ecological approaches, the social challenges faced by children, and new potential intervention methods.
PubMed: 37622816
DOI: 10.3390/bs13080676 -
Cortex; a Journal Devoted To the Study... Oct 2023People with aphantasia have a markedly impaired ability to form visual images in the mind's eye. Here, by testing people with and without aphantasia, we examine the...
People with aphantasia have a markedly impaired ability to form visual images in the mind's eye. Here, by testing people with and without aphantasia, we examine the relationship between visual imagery and face processing. We show that aphantasics have weaker face recognition than people with visual imagery, using both self-report (Prosopagnosia Index) and behavioural measures (Cambridge Face Memory Test). However, aphantasics nonetheless have a fully intact ability to construct facial composites from memory (i.e., composites produced using EFIT6 by aphantasics and imagers were rated as equally accurate in terms of their resemblance to a target face). Additionally, we show that aphantasics were less able than imagers to see the resemblance between composites and a target face, suggestive of potential issues with face matching (perception). Finally, we show that holistic and featural methods of composite construction using EFIT6 produce equally accurate composites. Our results suggest that face recognition, but not face composite construction, is facilitated by the ability to represent visual properties as 'pictures in the mind'. Our findings have implications for the study of aphantasia, and also for forensic settings, where face composite systems are commonly used to aid criminal investigations.
Topics: Humans; Facial Recognition; Imagery, Psychotherapy; Prosopagnosia; Recognition, Psychology; Self Report; Visual Perception
PubMed: 37597266
DOI: 10.1016/j.cortex.2023.06.015 -
Clinical Pediatrics Jun 2024
Topics: Humans; Aphasia; Headache; Prosopagnosia; Young Adult; Male; Female; Acute Disease; Diagnosis, Differential
PubMed: 37497923
DOI: 10.1177/00099228231190226